Embodiments of the invention generally relate to a method and system for compensating reactive power in power systems and in particular, to a method and system for compensating reactive power in solar power generation systems.
Power transmission and distribution grids transmit electrical energy from generating facilities to end users. Voltage management on a transmission and distribution system is one of the factors considered for the stable operation and design of the system. Reactive power flow may be influenced by the generator source, changes in the transmission and distribution system, the addition of shunt reactive elements, and loads, for example.
Reactive power is important from a standpoint of power delivery. In a typical power system reactive power flow has an influence on voltage. Since most transmission systems are inductive, increasing a reactive current component (i.e., capacitive volt-amperes reactive or VARs) will cause the voltage to rise. Conversely, decreasing a reactive power component (i.e., inductive VARs) will cause the voltage to decrease. Furthermore, excessive reactive power flow that causes rises in voltage may put undue stress on transmission lines, transformers and other electrical components.
Reactive power compensation techniques have been addressed by providing VAR support based on real power generation and power factor control. However, VAR support and power factor control has some shortcomings. For example, VAR support increases the reactive power and does not affect the real power. Therefore, total capability of the generators is not utilized since VAR support is proportional to the square of real and reactive power outputs. Further, power factor control may occasionally result in an undesirable action such as introducing capacitance to inherently maintain a desired voltage.
Therefore, there is a need for an enhanced reactive power control to dynamically address fluctuating conditions in power generating systems.